1 /*
2  * Freescale PowerQUICC Ethernet Driver -- MIIM bus implementation
3  * Provides Bus interface for MIIM regs
4  *
5  * Author: Andy Fleming <afleming@freescale.com>
6  * Modifier: Sandeep Gopalpet <sandeep.kumar@freescale.com>
7  *
8  * Copyright 2002-2004, 2008-2009 Freescale Semiconductor, Inc.
9  *
10  * Based on gianfar_mii.c and ucc_geth_mii.c (Li Yang, Kim Phillips)
11  *
12  * This program is free software; you can redistribute  it and/or modify it
13  * under  the terms of  the GNU General  Public License as published by the
14  * Free Software Foundation;  either version 2 of the  License, or (at your
15  * option) any later version.
16  *
17  */
18 
19 #include <linux/kernel.h>
20 #include <linux/string.h>
21 #include <linux/errno.h>
22 #include <linux/unistd.h>
23 #include <linux/slab.h>
24 #include <linux/interrupt.h>
25 #include <linux/init.h>
26 #include <linux/delay.h>
27 #include <linux/netdevice.h>
28 #include <linux/etherdevice.h>
29 #include <linux/skbuff.h>
30 #include <linux/spinlock.h>
31 #include <linux/mm.h>
32 #include <linux/module.h>
33 #include <linux/platform_device.h>
34 #include <linux/crc32.h>
35 #include <linux/mii.h>
36 #include <linux/phy.h>
37 #include <linux/of.h>
38 #include <linux/of_address.h>
39 #include <linux/of_mdio.h>
40 #include <linux/of_platform.h>
41 
42 #include <asm/io.h>
43 #include <asm/irq.h>
44 #include <asm/uaccess.h>
45 #include <asm/ucc.h>
46 
47 #include "gianfar.h"
48 #include "fsl_pq_mdio.h"
49 
50 struct fsl_pq_mdio_priv {
51 	void __iomem *map;
52 	struct fsl_pq_mdio __iomem *regs;
53 };
54 
55 /*
56  * Write value to the PHY at mii_id at register regnum,
57  * on the bus attached to the local interface, which may be different from the
58  * generic mdio bus (tied to a single interface), waiting until the write is
59  * done before returning. This is helpful in programming interfaces like
60  * the TBI which control interfaces like onchip SERDES and are always tied to
61  * the local mdio pins, which may not be the same as system mdio bus, used for
62  * controlling the external PHYs, for example.
63  */
64 int fsl_pq_local_mdio_write(struct fsl_pq_mdio __iomem *regs, int mii_id,
65 		int regnum, u16 value)
66 {
67 	/* Set the PHY address and the register address we want to write */
68 	out_be32(&regs->miimadd, (mii_id << 8) | regnum);
69 
70 	/* Write out the value we want */
71 	out_be32(&regs->miimcon, value);
72 
73 	/* Wait for the transaction to finish */
74 	while (in_be32(&regs->miimind) & MIIMIND_BUSY)
75 		cpu_relax();
76 
77 	return 0;
78 }
79 
80 /*
81  * Read the bus for PHY at addr mii_id, register regnum, and
82  * return the value.  Clears miimcom first.  All PHY operation
83  * done on the bus attached to the local interface,
84  * which may be different from the generic mdio bus
85  * This is helpful in programming interfaces like
86  * the TBI which, in turn, control interfaces like onchip SERDES
87  * and are always tied to the local mdio pins, which may not be the
88  * same as system mdio bus, used for controlling the external PHYs, for eg.
89  */
90 int fsl_pq_local_mdio_read(struct fsl_pq_mdio __iomem *regs,
91 		int mii_id, int regnum)
92 {
93 	u16 value;
94 
95 	/* Set the PHY address and the register address we want to read */
96 	out_be32(&regs->miimadd, (mii_id << 8) | regnum);
97 
98 	/* Clear miimcom, and then initiate a read */
99 	out_be32(&regs->miimcom, 0);
100 	out_be32(&regs->miimcom, MII_READ_COMMAND);
101 
102 	/* Wait for the transaction to finish */
103 	while (in_be32(&regs->miimind) & (MIIMIND_NOTVALID | MIIMIND_BUSY))
104 		cpu_relax();
105 
106 	/* Grab the value of the register from miimstat */
107 	value = in_be32(&regs->miimstat);
108 
109 	return value;
110 }
111 
112 static struct fsl_pq_mdio __iomem *fsl_pq_mdio_get_regs(struct mii_bus *bus)
113 {
114 	struct fsl_pq_mdio_priv *priv = bus->priv;
115 
116 	return priv->regs;
117 }
118 
119 /*
120  * Write value to the PHY at mii_id at register regnum,
121  * on the bus, waiting until the write is done before returning.
122  */
123 int fsl_pq_mdio_write(struct mii_bus *bus, int mii_id, int regnum, u16 value)
124 {
125 	struct fsl_pq_mdio __iomem *regs = fsl_pq_mdio_get_regs(bus);
126 
127 	/* Write to the local MII regs */
128 	return fsl_pq_local_mdio_write(regs, mii_id, regnum, value);
129 }
130 
131 /*
132  * Read the bus for PHY at addr mii_id, register regnum, and
133  * return the value.  Clears miimcom first.
134  */
135 int fsl_pq_mdio_read(struct mii_bus *bus, int mii_id, int regnum)
136 {
137 	struct fsl_pq_mdio __iomem *regs = fsl_pq_mdio_get_regs(bus);
138 
139 	/* Read the local MII regs */
140 	return fsl_pq_local_mdio_read(regs, mii_id, regnum);
141 }
142 
143 /* Reset the MIIM registers, and wait for the bus to free */
144 static int fsl_pq_mdio_reset(struct mii_bus *bus)
145 {
146 	struct fsl_pq_mdio __iomem *regs = fsl_pq_mdio_get_regs(bus);
147 	int timeout = PHY_INIT_TIMEOUT;
148 
149 	mutex_lock(&bus->mdio_lock);
150 
151 	/* Reset the management interface */
152 	out_be32(&regs->miimcfg, MIIMCFG_RESET);
153 
154 	/* Setup the MII Mgmt clock speed */
155 	out_be32(&regs->miimcfg, MIIMCFG_INIT_VALUE);
156 
157 	/* Wait until the bus is free */
158 	while ((in_be32(&regs->miimind) & MIIMIND_BUSY) && timeout--)
159 		cpu_relax();
160 
161 	mutex_unlock(&bus->mdio_lock);
162 
163 	if (timeout < 0) {
164 		printk(KERN_ERR "%s: The MII Bus is stuck!\n",
165 				bus->name);
166 		return -EBUSY;
167 	}
168 
169 	return 0;
170 }
171 
172 void fsl_pq_mdio_bus_name(char *name, struct device_node *np)
173 {
174 	const u32 *addr;
175 	u64 taddr = OF_BAD_ADDR;
176 
177 	addr = of_get_address(np, 0, NULL, NULL);
178 	if (addr)
179 		taddr = of_translate_address(np, addr);
180 
181 	snprintf(name, MII_BUS_ID_SIZE, "%s@%llx", np->name,
182 		(unsigned long long)taddr);
183 }
184 EXPORT_SYMBOL_GPL(fsl_pq_mdio_bus_name);
185 
186 
187 static u32 __iomem *get_gfar_tbipa(struct fsl_pq_mdio __iomem *regs, struct device_node *np)
188 {
189 #if defined(CONFIG_GIANFAR) || defined(CONFIG_GIANFAR_MODULE)
190 	struct gfar __iomem *enet_regs;
191 
192 	/*
193 	 * This is mildly evil, but so is our hardware for doing this.
194 	 * Also, we have to cast back to struct gfar because of
195 	 * definition weirdness done in gianfar.h.
196 	 */
197 	if(of_device_is_compatible(np, "fsl,gianfar-mdio") ||
198 		of_device_is_compatible(np, "fsl,gianfar-tbi") ||
199 		of_device_is_compatible(np, "gianfar")) {
200 		enet_regs = (struct gfar __iomem *)regs;
201 		return &enet_regs->tbipa;
202 	} else if (of_device_is_compatible(np, "fsl,etsec2-mdio") ||
203 			of_device_is_compatible(np, "fsl,etsec2-tbi")) {
204 		return of_iomap(np, 1);
205 	}
206 #endif
207 	return NULL;
208 }
209 
210 
211 static int get_ucc_id_for_range(u64 start, u64 end, u32 *ucc_id)
212 {
213 #if defined(CONFIG_UCC_GETH) || defined(CONFIG_UCC_GETH_MODULE)
214 	struct device_node *np = NULL;
215 	int err = 0;
216 
217 	for_each_compatible_node(np, NULL, "ucc_geth") {
218 		struct resource tempres;
219 
220 		err = of_address_to_resource(np, 0, &tempres);
221 		if (err)
222 			continue;
223 
224 		/* if our mdio regs fall within this UCC regs range */
225 		if ((start >= tempres.start) && (end <= tempres.end)) {
226 			/* Find the id of the UCC */
227 			const u32 *id;
228 
229 			id = of_get_property(np, "cell-index", NULL);
230 			if (!id) {
231 				id = of_get_property(np, "device-id", NULL);
232 				if (!id)
233 					continue;
234 			}
235 
236 			*ucc_id = *id;
237 
238 			return 0;
239 		}
240 	}
241 
242 	if (err)
243 		return err;
244 	else
245 		return -EINVAL;
246 #else
247 	return -ENODEV;
248 #endif
249 }
250 
251 static int fsl_pq_mdio_probe(struct platform_device *ofdev)
252 {
253 	struct device_node *np = ofdev->dev.of_node;
254 	struct device_node *tbi;
255 	struct fsl_pq_mdio_priv *priv;
256 	struct fsl_pq_mdio __iomem *regs = NULL;
257 	void __iomem *map;
258 	u32 __iomem *tbipa;
259 	struct mii_bus *new_bus;
260 	int tbiaddr = -1;
261 	const u32 *addrp;
262 	u64 addr = 0, size = 0;
263 	int err;
264 
265 	priv = kzalloc(sizeof(*priv), GFP_KERNEL);
266 	if (!priv)
267 		return -ENOMEM;
268 
269 	new_bus = mdiobus_alloc();
270 	if (!new_bus) {
271 		err = -ENOMEM;
272 		goto err_free_priv;
273 	}
274 
275 	new_bus->name = "Freescale PowerQUICC MII Bus",
276 	new_bus->read = &fsl_pq_mdio_read,
277 	new_bus->write = &fsl_pq_mdio_write,
278 	new_bus->reset = &fsl_pq_mdio_reset,
279 	new_bus->priv = priv;
280 	fsl_pq_mdio_bus_name(new_bus->id, np);
281 
282 	addrp = of_get_address(np, 0, &size, NULL);
283 	if (!addrp) {
284 		err = -EINVAL;
285 		goto err_free_bus;
286 	}
287 
288 	/* Set the PHY base address */
289 	addr = of_translate_address(np, addrp);
290 	if (addr == OF_BAD_ADDR) {
291 		err = -EINVAL;
292 		goto err_free_bus;
293 	}
294 
295 	map = ioremap(addr, size);
296 	if (!map) {
297 		err = -ENOMEM;
298 		goto err_free_bus;
299 	}
300 	priv->map = map;
301 
302 	if (of_device_is_compatible(np, "fsl,gianfar-mdio") ||
303 			of_device_is_compatible(np, "fsl,gianfar-tbi") ||
304 			of_device_is_compatible(np, "fsl,ucc-mdio") ||
305 			of_device_is_compatible(np, "ucc_geth_phy"))
306 		map -= offsetof(struct fsl_pq_mdio, miimcfg);
307 	regs = map;
308 	priv->regs = regs;
309 
310 	new_bus->irq = kcalloc(PHY_MAX_ADDR, sizeof(int), GFP_KERNEL);
311 
312 	if (NULL == new_bus->irq) {
313 		err = -ENOMEM;
314 		goto err_unmap_regs;
315 	}
316 
317 	new_bus->parent = &ofdev->dev;
318 	dev_set_drvdata(&ofdev->dev, new_bus);
319 
320 	if (of_device_is_compatible(np, "fsl,gianfar-mdio") ||
321 			of_device_is_compatible(np, "fsl,gianfar-tbi") ||
322 			of_device_is_compatible(np, "fsl,etsec2-mdio") ||
323 			of_device_is_compatible(np, "fsl,etsec2-tbi") ||
324 			of_device_is_compatible(np, "gianfar")) {
325 		tbipa = get_gfar_tbipa(regs, np);
326 		if (!tbipa) {
327 			err = -EINVAL;
328 			goto err_free_irqs;
329 		}
330 	} else if (of_device_is_compatible(np, "fsl,ucc-mdio") ||
331 			of_device_is_compatible(np, "ucc_geth_phy")) {
332 		u32 id;
333 		static u32 mii_mng_master;
334 
335 		tbipa = &regs->utbipar;
336 
337 		if ((err = get_ucc_id_for_range(addr, addr + size, &id)))
338 			goto err_free_irqs;
339 
340 		if (!mii_mng_master) {
341 			mii_mng_master = id;
342 			ucc_set_qe_mux_mii_mng(id - 1);
343 		}
344 	} else {
345 		err = -ENODEV;
346 		goto err_free_irqs;
347 	}
348 
349 	for_each_child_of_node(np, tbi) {
350 		if (!strncmp(tbi->type, "tbi-phy", 8))
351 			break;
352 	}
353 
354 	if (tbi) {
355 		const u32 *prop = of_get_property(tbi, "reg", NULL);
356 
357 		if (prop)
358 			tbiaddr = *prop;
359 
360 		if (tbiaddr == -1) {
361 			err = -EBUSY;
362 			goto err_free_irqs;
363 		} else {
364 			out_be32(tbipa, tbiaddr);
365 		}
366 	}
367 
368 	err = of_mdiobus_register(new_bus, np);
369 	if (err) {
370 		printk (KERN_ERR "%s: Cannot register as MDIO bus\n",
371 				new_bus->name);
372 		goto err_free_irqs;
373 	}
374 
375 	return 0;
376 
377 err_free_irqs:
378 	kfree(new_bus->irq);
379 err_unmap_regs:
380 	iounmap(priv->map);
381 err_free_bus:
382 	kfree(new_bus);
383 err_free_priv:
384 	kfree(priv);
385 	return err;
386 }
387 
388 
389 static int fsl_pq_mdio_remove(struct platform_device *ofdev)
390 {
391 	struct device *device = &ofdev->dev;
392 	struct mii_bus *bus = dev_get_drvdata(device);
393 	struct fsl_pq_mdio_priv *priv = bus->priv;
394 
395 	mdiobus_unregister(bus);
396 
397 	dev_set_drvdata(device, NULL);
398 
399 	iounmap(priv->map);
400 	bus->priv = NULL;
401 	mdiobus_free(bus);
402 	kfree(priv);
403 
404 	return 0;
405 }
406 
407 static struct of_device_id fsl_pq_mdio_match[] = {
408 	{
409 		.type = "mdio",
410 		.compatible = "ucc_geth_phy",
411 	},
412 	{
413 		.type = "mdio",
414 		.compatible = "gianfar",
415 	},
416 	{
417 		.compatible = "fsl,ucc-mdio",
418 	},
419 	{
420 		.compatible = "fsl,gianfar-tbi",
421 	},
422 	{
423 		.compatible = "fsl,gianfar-mdio",
424 	},
425 	{
426 		.compatible = "fsl,etsec2-tbi",
427 	},
428 	{
429 		.compatible = "fsl,etsec2-mdio",
430 	},
431 	{},
432 };
433 MODULE_DEVICE_TABLE(of, fsl_pq_mdio_match);
434 
435 static struct platform_driver fsl_pq_mdio_driver = {
436 	.driver = {
437 		.name = "fsl-pq_mdio",
438 		.owner = THIS_MODULE,
439 		.of_match_table = fsl_pq_mdio_match,
440 	},
441 	.probe = fsl_pq_mdio_probe,
442 	.remove = fsl_pq_mdio_remove,
443 };
444 
445 module_platform_driver(fsl_pq_mdio_driver);
446 
447 MODULE_LICENSE("GPL");
448